(中南大学 化学化工学院,长沙 410083)
摘 要: 合成了一种新型的三唑硫酮类表面活性剂—3-己基-4-氨基-1,2,4-三唑-5-硫酮(HATT),通过红外光谱和核磁共振氢谱及磁谱对其结构进行了表征,研究其在黄铜矿表面的吸附动力学和热力学。结果表明:黄铜矿吸附HATT优选的pH值为4~8,吸附量随着温度的升高而增大;吸附过程符合准二级动力学方程,吸附活化能为13.06 kJ/mol;HATT在黄铜矿表面的吸附等温线符合Langmuir模型,吸附焓变ΔH为71.52 kJ/mol,熵变ΔS为348.7 J/(mol·K),吸附自由能变ΔG为-28.95 kJ/mol(298K)。HATT可能以单分子层化学吸附于黄铜矿表面,吸附为自发的吸热过程。FTIR光谱分析进一步证实HATT以化学方式吸附在黄铜矿的表面。浮选试验结果也表明,HATT是黄铜矿的优良捕收剂。
关键字: 3-己基-4-氨基-1,2,4-三唑-5-硫酮;黄铜矿;热力学;动力学; 吸附
(School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China)
Abstract:A novel surfactant, 3-hexyl-4-amino-1,2,4-triazole-5-thione (HATT) was synthesized and characterized by infrared spectroscopy, 1HNMR and 13CNMR. And its adsorption kinetics and thermodynamics on the chalcopyrite surface were evaluated. The results indicate that the preferable pH values for HATT adsorption on chalcopyrite surface are 4-8 and the adsorption amount increases with increasing temperature. The adsorption process conforms to the pseudo-second-order kinetics equation and the adsorption activation energy is 13.06 kJ/mol. The adsorption isotherm agrees well with Langmuir model and the thermodynamics parameters ΔH, ΔS and ΔG are 71.52 kJ/mol, 348.7 J/(mol·K) and -28.95 kJ/mol (298K), respectively. The adsorption of HATT on the chalcopyrite surface is a spontaneous endothermic monolayer chemisorption. The FTIR spectra further verify the chemisorption process. The flotation results also show that HATT is a superior collector for chalcopyrite.
Key words: 3-hexyl-4-amino-1,2,4-triazole-5-thione; chalcopyrite; thermodynamics; kinetics; adsorption